Trade unions are calling for Sports Direct shareholders to vote in favour of a review into how the company treats workers, after figures from the retailer's annual report showed the number of injuries in its workplaces are significantly higher than the industry average.

According to the TUC, there are 6.6 injuries per 100,000 hours worked among Sports Direct's warehouse staff - nearly triple the typical rate seen in the agriculture sector, widely regarded as one of the least safe industries for workers.

In the embattled company's retail, office and distribution division, there are 2.7 injuries per 100,000 hours worked compared to the average of 1.4 across the rest of the industry.

A letter written to Sports Direct shareholders by the Trade Union Share Owners group (TUSO) also highlights "incredibly worrying" turnover rates among its workforce.

The chain's annual report says 22% of its salaried staff left the company in the 2016 financial year, compared to 19% in 2015.

This figure is almost three times higher than the average turnover of 8% as calculated by the Chartered Institute of Personnel and Development in a survey last year.

Frances O'Grady, general secretary of the TUC, said: "Sports Direct has shown a consistent disregard for the wellbeing of its staff. These abysmal figures show that the company is performing far worse than other companies in the same sector.

"It's time for Sports Direct to shape up. An independent investigation is a necessary first step to fixing the endemic problems at Sports Direct."

TUSO says the retailer's practices pose a long-term risk to investors, and says it is the responsibility of shareholders to show workers they acknowledge change is needed.

Under the resolution put forward by the group, the independent review would be expected to report back within six months of Sports Direct's AGM in September.

Video:July: Sports Direct Accused Of Victorian Workhouse Practises

On Monday, Sports Direct agreed to grant thousands of workers back pay totalling about £1m following the admission that the company had not been paying the minimum wage.

Agency workers and contracted staff who are employed at the company's Shirebrook warehouse in Derbyshire will be reimbursed, and some could receive up to £1,000.

Sports Direct boss Mike Ashley admitted to MPs that his company had subjected workers to searches after the end of their shifts, during which they were not paid for their time.